The following account of the prior art relates to one of the areas of application of the present application, hearing aids.
Detection of wind noise and subsequent minimization of its influence on a target signal, e.g. in a hearing aid, such as a head set or a hearing instrument, has been dealt with in a number publications. EP1448016A1 deals for example with a device for detecting the presence of wind noise in an array of microphones. The microphones each generate their time dependant signals, which are fed to a signal processing device providing one or more output signals. The signal processing device has means for generating a time dependant cross correlation function between a first and a second microphone signal and, means for generating a signal corresponding to a time dependant auto correlation function of either the first or the second of the microphone signals. Further the signal processing device is configured to detect a condition that the auto correlation function is substantially higher than the cross correlation function, which is indicative of the presence of wind noise.
US20120253798A1 deals with an arrangement of two microphones where one is multiplied by a factor α, the other by 1−α, and the resulting signals are summed, and wherein α is determined by an adaptive filter for computing an updated value of α to minimize the energy of the summed signal, the updated value of α based on the summed signal and the first and second input signals.
GB2453118A deals with an apparatus for suppression of wind noise in multi-microphone systems, e.g. for generating a speech audio signal from multiple microphones with suppressed wind noise. A combine processor generates combined subband signals from first and second microphone signals split into first and second frequency domain subbands by, for each subband, selecting a subband magnitude for the combined subband signal as a lowest magnitude of a subband magnitude for the first frequency domain subband signal and a subband magnitude for the second frequency domain subband signal.
WO2008041730A1 deals with a method of detecting wind noise including calculating a correlation coefficient between two microphone signals and a number of specific parameters of the two signals.
EP1339256A2 deals with a microphone signal connected to a controllable high pass filter. The control input of the high-pass filter is generated via a statistics evaluating unit, which continuously monitors the behavior of the input signal during a predetermined amount of time. The high-pass filter characteristic is adjusted so as to minimize the energy of the output of the HP-filter.